RESUMO
OBJECTIVES: To find an association between self-reported change in oral health and dental treatment volume. METHODS: Baseline data were obtained from the Tasmanian component of the National Survey of Adult Oral Health 2004-06 and 12-month follow-up data from service use logbooks and mail self-complete questionnaires. The global oral health transition statement indicated change in oral health. Many putative confounders were analyzed and Poisson regression with robust variance estimation was used to calculate the prevalence ratios and 95 percent confidence intervals for bivariate- and multivariate-adjusted relationships. RESULTS: One-eighth (12.4 percent) of the participants reported that their oral health had improved. Over half visited a dentist (n=176, 52.6 percent), of whom 105 received less than six dental services and 71 received six or more dental services. Baseline oral disease (P=0.01), having a treatment need (P<0.01), usually visiting a dentist for a problem (P<0.05), and having a lot of difficulty paying a $100 dental bill (P=0.01) were significantly associated with the same or worsening oral health. The regression model indicated that having six or more dental services (P<0.01) was significantly associated with improvement in oral health, indicating a threshold effect. Usually visiting a dentist for a check-up was significantly associated with improvement in oral health (P<0.01). CONCLUSION: Having six or more dental services was significantly associated with a greater self-reported improvement in oral health than having less than six dental services. The greater prevalence ratios with increasing dental service volume suggested a threshold effect.